What are secondary lesions?
They typically elvove from a primary lesion or as a consequence to the patients activities (scratching, infections, …).
Which are the secondary lesions?
- Scale
- Crust
- Lichenification
- Fissure
- Erosion
- Ulcer
- Scar
- Atrophy
What is a scale?
Examples?
Visible fragments of the outermost layer (stratum corneum) of the skin as it is shed (desqumating) from the skin. This happens when it proliferates faster than normal. A rash consisting of scales is called papulosquamous exanthema.
Examples:
Solar dermatitis
Psoriasis vulgaris
Pityriasis rosea

What is a crust?
Examples?
Drying of liquid debris (serum, blood, pus) on surrounding skin. Can be due rupture of vesicles or pustules.
Examples:
Impetigo
Ecthyma

What is lichenification?
Examples?
Thickening of the skin surface over time. Increase of skin markings: wrinkles, skin lines, … Usually due to chronic scratching or rubbing of an area.
Examples:
Atopic eczema/dermatitis
Chronic contact dermatitis

What is a fissure?
Examples?
It is the linear splitting of the skin surface extending in the epidermis to the dermis or deeper. Usually caused by repetitive trauma to the skin. Usually associated to other skin diseases.
Examples:
Crohn’s disease
Hailey-hailey disease

What is an erosion?
Examples?
Loss of superficial epidermis by friction or pressure. Sharply-defined, red and oozes serum. Always heals without a scar.
Examples:
Bullous pemphigoid
Pemphigus vulgaris
Contagious impetigo

What is an ulcer?
Examples?
Loss of skin extending into dermis and deeper. Always occur within pathological altered tissue and thus always secondary phenomena. They can be the continuation of erosisons. Always resolves with a scar.
Examples:
Leg ulcer
Grade III burn
Ecthyma

What is a scar?
Examples?
Fibrous regeneration tissue due to wound repair in the skin replacing normal skin after injury of the dermis and/or the subcutis.
Examples:
Scarring alopecia
Trauma
Keloid

What is atrophy?
Examples?
Partial or complete wasting away (shrinking, involution, incomplete development) of the skin
Examples:
Lichen sclerosus et atrophicus
Scar
Steroid atrophy
Chronic discoid lupus erythematosus